Track type machines, for example dozers, excavators, and skid-steer loaders, are commonly used in applications where traction is critical or low ground pressure is important. These machines include a frame that supports an internal combustion engine. The machines include left and right undercarriages that are powered by the engine and enable movement of the machine along a ground surface. The left and right undercarriages are rigidly mounted at one end to the frame and are free to pivot in a vertical direction about the mounting location. Each of the undercarriages includes one or more sprockets driven by the engine, and an idler wheel operatively connected to either the frame of the machine or to the sprocket via an idler frame assembly. The idler frame assembly includes a plurality of upper carriers and lower rollers that support an endless track wrapped in a loop around the sprocket and idler.
During operation of a track type machine, components of the undercarriage undergo wear, which may cause a decrease in distance between a bottom surface of the lower rollers and a periphery of the idler wheel. In some instances, this wear can be significant enough that the idler wheel does not engage the track properly and may consequently disrupt engagement of the lower rollers with the track. To avoid such a scenario, removable spacer members or shims are provided for improved spacing between worn components of the assembly. The shims may be used to assist positioning of the idler wheel of a track roller frame associated with the track type machine. The shims may also allow for the idler wheel to slide within the shims for tensioning of the track of the machine. Such shims or spacer members are used as a sacrificial part to avoid wearing of the track roller frame.
However, use of such spacer members is less than optimal, as the spacer members are difficult to install and difficult to retain in position as the components continue to wear and as the idler translates longitudinally relative to a sprocket of the machine. Further, as the machine operates, the shims may easily get lost if they are not secured to the track roller frame, for example via fastening through bolts, welds, etc.